Minimum host gcc version? (was: [PATCH] qemu-native: set ld.bfd, fix cflags, and set some environment vars)

[Peter Kjellerstedt <peter.kjellerstedt@axis.com>]

> -----Original Message-----
> From: openembedded-core-bounces@lists.openembedded.org
> [mailto:openembedded-core-bounces@lists.openembedded.org] On Behalf Of
> Stephen Arnold
> Sent: den 19 juni 2016 21:40
> To: openembedded-core@lists.openembedded.org
> Cc: Stephen Arnold; Stephen Arnold
> Subject: [OE-core] [PATCH] qemu-native: set ld.bfd, fix cflags, and set
> some environment vars
> 
> The main thing is build failures with gold linker, but qemu is also
> a little too aggressive at finding random tools on the build host, so
> we also set the build env for qemu-native and make sure it doesn't
> reset its own (hard-coded) cflags when we don't want it to.
> 
> Signed-off-by: Stephen Arnold <sarnold@vctlabs.com>
> 
> The cflags patch was imported from Gentoo Portage and has been
> manitained over several versions; this version was rebased against
> upstream qemu git.
> 
> Upstream-Status: Inappropriate
>  - Patch addresses distribution maintenance and build environment
>    sanity.
> 
> Signed-off-by: Stephen Arnold <nerdboy@gentoo.org>
> ---
>  meta/recipes-devtools/qemu/qemu.inc                | 13 +++++++--
>  .../qemu/qemu/qemu-2.6.0-cflags.patch              | 31
> ++++++++++++++++++++++
>  meta/recipes-devtools/qemu/qemu_2.6.0.bb           |  1 +
>  3 files changed, 43 insertions(+), 2 deletions(-)
>  create mode 100644 meta/recipes-devtools/qemu/qemu/qemu-2.6.0-
> cflags.patch
> 
> diff --git a/meta/recipes-devtools/qemu/qemu.inc b/meta/recipes-
> devtools/qemu/qemu.inc
> index bf689bb..d5925fd 100644
> --- a/meta/recipes-devtools/qemu/qemu.inc
> +++ b/meta/recipes-devtools/qemu/qemu.inc
> @@ -30,8 +30,12 @@ SRC_URI_append_class-native = "\
> 
>  EXTRA_OECONF += "--target-list=${@get_qemu_target_list(d)} --disable-werror  --disable-bluez --disable-libiscsi --with-system-pixman --extra-cflags='${CFLAGS}'"
> 
> -EXTRA_OECONF_class-nativesdk = "--target-list=${@get_qemu_target_list(d)} --disable-werror \
> -				"
> +EXTRA_OECONF_class-nativesdk = "--target-list=${@get_qemu_target_list(d)} --disable-werror"
> +
> +EXTRA_OEMAKE_append_class-native = " LD='${LD}' AR='${AR}' OBJCOPY='${OBJCOPY}' LDFLAGS='${LDFLAGS}'"
> +
> +LDFLAGS_append_class-native = " -fuse-ld=bfd"

The use of -fuse-ld=bfd causes a build a failure with gcc 4.7.2 
that I still use as host compiler. Was it intentional to increase 
the minimum required host compiler version? If not, can this 
option be made conditional for compilers that do not support it?

//Peter